Prior to the introduction of portable-printing machines, such as a typewriter, the term “watermark” was used to describe a mark or image in paper visible when the paper is held up to a light source. The “watermark” resulted from differences in thickness usually produced by pressure of a projecting design in a mold or on a processing roll in association with a printing press that imprinted an image on a paper medium. An observer of a document with a unique “watermark” could match the “watermark” with the mark associated with a particular publisher or printer to identify the source and/or authenticate the document.
While watermarks are still used today to both identify the source and to authenticate a document (e.g., a bank draft), the proliferation of relatively low-cost high-quality printing and color-copying devices coupled with advances in computer technology, including the networking of computing devices, have significantly undermined the ability of a visible watermark to identify a particular source and/or authenticate a particular document. Consequently, visible watermarks are no longer as heavily relied upon for identifying authors of documents and authenticating original documents because of the relative ease with which visible watermarks can be removed from a digital representation of an image. Once the visible watermark is effectively removed from the digital representation, unscrupulous parties can make copies of, and/or generate derivative works from, the underlying image, possibly violating the author's copyrights in the original document or image. Not only can an individual with a computing device and a printer violate an author's copyrights in a work, but the networking of computing devices permits an unscrupulous party to post the author's work on a publicly-accessible data-storage device for others to partake as well.
In response, a number of methods have been developed to protect copyrights of images, music, and the like, that can be stored on computing devices accessible via wide-area networks such as the Internet. One response is to encode the images or files. These cryptographic protection methods permit access to the encoded or encrypted data, to holders of a key. Once, a party acquires the key, the underlying image, audio, video, and multimedia data can be copied and distributed at will. Another response is to add a digital watermark into the various image, music, document, multimedia, or other files that are to be protected.
Unlike cryptographic methods that do not have a mechanism for tracking reproduction of a file, digital watermarks, in the form of an invisible-identification code that can be permanently embedded in the data, have the capability to identify each authorized purchaser of a protected file. Because the contents of the digital watermark are placed in perceptually significant components of the data, the removal of the watermark makes appreciation of the underlying data protected by the digital watermark virtually impossible. Modification of these components can lead to perceptual degradation of the underlying data. To avoid this, a digital watermark is inserted into the spectral components of the data using techniques analogous to spread spectrum communications. While not visible or audible to human senses, the digital watermark is discernible when operated upon by common data and geometric manipulations such as digital-to-analog and analog-to-digital conversion, resampling, and requantization, including printing and compression, rotation, translation, cropping and scaling.
Attempts to remove the digital watermark from an image will result in a noticeable degradation in image or signal quality well before the digital watermark is lost, thereby rendering the underlying data useless. Retrieval of the digital watermark unambiguously identifies the owner, and the digital watermark can be constructed to make counterfeiting almost impossible. Because the same digital watermarking algorithm can be applied to multiple file types (e.g., document, audio, photo, image, and video) with only minor modifications, the resulting digital watermark is appropriate for protecting various products that may be digitally stored and accessible via the Internet.
Because the digital watermark allows unique identification of copyright owners, buyers, and distributors, it provides a strong deterrent to illegal copying. Many believe that this digital-watermarking technique is an enabling technology that will help create a secure-business environment for copyright holders using the Internet.
It is still desirable however to mark documents and/or other image files with visible-graphic and/or text-based watermarks to identify the state or nature of the underlying document. For example, it is often desirable to mark a preliminary version of a document with a watermark containing the term “Draft” as a visible indication that the reader is observing a document in work. In addition, it is often desirable to mark documents with a classification level, such as, “Confidential” or “Proprietary.” Document authors often add these and other classifications to their work product (e.g., documents, images, and the like) for use as a quick reference in identifying a limited group of intended recipients of the underlying message.
Some conventional-printer drivers support the addition of a watermark to data associated with a particular print task (i.e., a request to print a document file). A driver is a computer program that controls a device. Peripheral devices associated with computers, whether printers, disk drives, keyboards, pointing devices, and the like, are supported by a driver program. Many drivers, such as keyboard, disk drive, and pointing device drivers, are supplied with the operating system. For other devices, a driver program may have to be loaded before the associated peripheral device will operate with the computer.
A driver acts like a language translator between the peripheral device and programs that use the device. Each peripheral device has its own set of specialized commands that only its driver knows. In contrast, most application programs access devices using generic commands. The driver, therefore, accepts generic commands from an application program operating on the computer and translates the commands into the specialized commands for the particular peripheral device.
Often, a printer driver that supports watermarks for use with a particular printer model does not even exist. In cases where a printer driver has been created for use with a particular printer model, the driver is located and installed. Even when they exist, conventional-printer drivers that support the addition of a visible watermark in a hard-copy product have a number of limitations. First, the drivers are located and installed. Second, conventional printers and associated drivers do not include the capability to integrate a watermark across multiple printers. Because printer drivers as explained above are generated for each particular type of printer, a watermark that has been added or defined for use with a first printer is not automatically usable with another printer. Stated another way, an operator of a computing system that desires to integrate a particular watermark with multiple printers must recreate the watermark with each printer. Third, conventional printers and their drivers do not support a true “preview” of the expected results. Because typical printer-driver user interfaces do not include the capability to retrieve an actual data document while integrating a watermark, a “preview” step generally results in a rendition of the location, color, and brightness of the watermark on a blank page. Only after a user of the software selects the “print” option is the data file acquired by the driver and forwarded by the driver to the printing device. At the time the data file is acquired by the driver, printing has already been initiated.
Visible watermarks can also be integrated with the contents of a document or image file using various commercially-available word processing and desktop-publishing application programs. Some of these applications, such as PageMaker®, commercially marketed by the Aldus Corporation of Seattle, Wash., U.S.A. and FinePrint™ by FinePrint Software, LLC (http://www.fineprint.com/) of San Francisco, Calif., U.S.A. provide an interface wherein a user of the application can generate and store a graphic image for use as a watermark.
A user of the FinePrint application is provided an interface with which the user interacts with the FinePrint application to define one or more watermarks. Each watermark contains a certain font type, font size, rotation, color, and text. The FinePrint application permits the user to select a previously defined watermark. Once a watermark has been defined by the user, the FinePrint™ “capture” function may be used to deliver the data intended for integration with the defined watermark to the FinePrint application. The FinePrint application then provides a pseudo preview of the data selected for the print job together with the selected watermark. However, the pseudo preview does not account for specific characteristics (e.g., paper type) of the destination printer. Thus, conventional-software applications require installation of the application software, installation of specialized drivers, and multiple user-intervention steps to integrate, preview, and generate a hard-copy product with the watermark.
Despite the capabilities now available via printer drivers and software applications to add visible watermarks to a hard-copy rendition of a data file, there still is a need for improved systems and methods for seamlessly integrating a watermark with an image file.